The science of predicting tropical storms and hurricanes has improved greatly in recent years, but it still isn’t exact. That’s why storm maps show not a straight-line path of a hurricane’s progress but a tadpole-shaped “cone of uncertainty.” The area inside the cone is the danger zone, and the size of each circle within it “is set so that two-thirds of historical official forecast errors over a 5-year sample fall within the circle,” according to a National Hurricane Center explanation.
The cone of uncertainty was in the news last week as Hurricane Dorian, a Category 5 storm, bore down on the southeastern United States after devastating the Bahamas. On September 1, President Trump tweeted that “in addition to Florida - South Carolina, North Carolina, Georgia, and Alabama, will most likely be hit (much) harder than anticipated.” Whoops. Alabama had never been included in the forecast, or positioned within many miles of the cone of uncertainty. Trump apparently invented the “prediction.”
The National Weather Service in Birmingham, Alabama, immediately reassured Alabamians that their state would “NOT see any impacts from #Dorian.” The NWS, as its name indicates, is an agency of the federal government. Nevertheless, Trump would not be contradicted. In a move that could have been dictated by Stalin, or Orwell, he made up his own alternative weather facts, and a map to support them.
On September 4, President Trump displayed a doctored National Hurricane Center map dated August 29 that depicts Hurricane Dorian’s cone of uncertainty along with a bulbous black-outlined annex of uncertain origin and dubious credibility. Source: Politico
Because the doctored area of the map appeared to have been drawn with a black Sharpie pen—the president’s preferred implement for signing ceremonies—the event was quickly dubbed #Sharpiegate. (For more about the use of the -gate suffix to denote scandals, see this 2010 Language Log post.)
The memes quickly followed.
But the matter was no joke, especially after the National Oceanic and Atmospheric Administration on September 6 issued a public statement contradicting the NWS tweet (which it called “opinion”) and supporting, in lickspittle fashion, the president’s baseless claim. Also on September 6, John Cassidy wrote in the New Yorker:
[E]ven if we accept that alarming Alabama residents about Hurricane Dorian’s path was one of Trump’s lesser sins, in the scheme of things, Trump’s angry reaction to being called out on it highlighted something more consequential: the extent to which the President’s attacks on the press have expanded and intensified.
“Cone of uncertainty” originated not in meteorology but in the field of project management, where it refers to the evolution of the amount of best-case uncertainty for a project. The term first appeared in print in 1958, in the Industrial & Engineering Chemistry journal, and has since been used in software engineering as well. In those fields, the size of the cone decreases as the project progresses, whereas with hurricane predictions it’s the future of the storm that is increasingly uncertain. Other names for the meteorological cone of uncertainty include Error Cone, Cone of Probability, CONUS, and (my favorite) the Cone of Death.
Uncertainty is a popular topic in the sciences.
The Heisenberg uncertainty principle, named for the physicist Werner Heisenberg, says that “the more precisely that you know the position of a particle, the less precisely you can know its momentum, and vice versa.” Source
And cones are well distributed in popular culture.
Maxwell Smart and Chief in the Cone of Silence on an episode of “Get Smart” (1965-1970; created by Mel Brooks and Buck Henry)
Dug the dog in the cone of shame in the Pixar animated film Up (2009)